Car accidents caused by under-inflated tires led to government legislation requiring that passenger cars be equipped with a tire pressure monitoring system (TPMS). For example, multiple deaths that occurred from rollovers due to tire failure of Firestone tires led to the Firestone recall, which pushed the United States Congress to pass the Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act. This Act mandated the use of a TPMS technology to help alert drivers of under-inflation events.
TPMS technology can be divided into direct and indirect systems. Indirect systems have been largely regarded as inaccurate due to their methods of measuring air pressures by monitoring individual wheel rotational speeds and other signals available outside of the tire itself. Direct systems are preferable over indirect systems because of their better accuracy in monitoring tire pressures.
Direct TPMS utilizes physical pressure sensors on each tire, either internally or externally. The sensors measure the tire pressure in each tire and report it to the vehicle's instrument cluster or a corresponding monitor. Some sensors are also capable of measuring the temperature inside the tire. These sensors can identify under-inflation in any combination, of one tire or all four, simultaneously. A typical pressure sensor is connected to a tire valve. However, when the valve breaks, the sensor would normally have to be replaced. Replacement of the pressure sensor is expensive and time-consuming since a new sensor would need to be reprogrammed. Hence there is a need for a system that allows the tire pressure sensor to be mounted more conveniently.
Any feature or combination of features described herein are included within the scope of the present invention provided that the features included in any such combination are not mutually inconsistent as will be apparent from the context, this specification, and the knowledge of one of ordinary skill in the art. Additional advantages and aspects of the present invention are apparent in the following detailed description and claims.